Micro-electro-mechanical systems (MEMS) may widely be used in technical devices. There may be for example MEMS microphones or other devices, such as for example a pressure sensor, which may be used in mobile devices such as mobile phones, such as for example smartphones, tablet PCs, pagers, portable PCs, Headsets, etc. Such a microphone may also be called microphone chip or microphone. A pressure-sensitive membrane, for example a diaphragm, is usually etched directly into a chip, for example a silicon chip, by MEMS techniques, and is usually accompanied with an integrated preamplifier. Most MEMS microphones are variants of the so-called condenser microphone design. MEMS microphones often have built in analog-to-digital converter (ADC) circuits on the same IC chip making the chip become a digital microphone and so more readily integrated with modern digital products mentioned above.
The usage of a conventional MEMS microphone may often be limited by the thickness of the corresponding substrate. Additionally, a thick substrate may lead to a small back volume behind the microphone in the corresponding device which may contribute to a low signal-to-noise ratio. However, the thinner the substrate is, the more difficult the handling of the substrate may become, because the substrate may be more sensitive against external mechanical influences during production and assembly. Therefore, a conventional microphone includes a substrate having a thickness not smaller than 300 μm.